6v53t advanced timing or standard?

Still assembling a 6v53t at a snail’s pace. Trying to decide whether to advance the timing or not. N70 injectors, twin turbo (factory set up), 1 3/8” pin turbo trunk pistons, natural blower, silent gears, V7L cams, standard liners. I know 1 1/2” or cross heads would be better but it’s what I’ve got and it won’t be a work truck. Probably going in a c1800 with a road ranger. The manual doesn’t say whether I should or shouldn’t, the subject seems to divide opinion strongly. What is the wisdom on the subject of this board?

Also a natural with N50s with early heats but I’m pretty sure standard timing is best for it? It’s going in a 6x6 army acco.

.This is the opinion of this bloke.............a lot agree......... but it is your call............



Sorry it is a bit hard to see............
..................Billy................

Greetings. When I was on the tools at Detco/MTU/Penske I rebuilt I don't know how many 6v53T's for the Defence Dept and they had standard timing with C55 injectors {I think}, by-pass blower, single turbo, crosshead pistons and they were good for 270 - 290 horses @ the flywheel- depending on the weather when being thrashed on the dyno. And to think back in the 70's an 8v71 with N60 injectors gave you 290hp { I think} so if the truck is not going to be worked I'd stick with standard. I'll try to get some snaps of the timing marks- I sent a message to the young fella to forward me some pics from the build book that I made that he now uses. The young fella dyno'd all of my engines and he had no fear of flogging the guts out of it as he didn't build the engine. Geez they sounded good on the dyno @ full noise. I have part numbers for the one piece aluminum rocker covers to suit jake brakes and all sorts of shit out in the shed if you need a heads up on part numbers. Next time, Pete

Overlander provided these for posting-

BillyP wrote:

.This is the opinion of this bloke.............a lot agree......... but it is your call............

Sorry it is a bit hard to see............
..................Billy................

Thanks Billy, that Leid bloke probably does know what he’s on about!

overlander wrote:

Greetings. When I was on the tools at Detco/MTU/Penske I rebuilt I don't know how many 6v53T's for the Defence Dept and they had standard timing with C55 injectors {I think}, by-pass blower, single turbo, crosshead pistons and they were good for 270 - 290 horses @ the flywheel- depending on the weather when being thrashed on the dyno. And to think back in the 70's an 8v71 with N60 injectors gave you 290hp { I think} so if the truck is not going to be worked I'd stick with standard. I'll try to get some snaps of the timing marks- I sent a message to the young fella to forward me some pics from the build book that I made that he now uses. The young fella dyno'd all of my engines and he had no fear of flogging the guts out of it as he didn't build the engine. Geez they sounded good on the dyno @ full noise. I have part numbers for the one piece aluminum rocker covers to suit jake brakes and all sorts of shit out in the shed if you need a heads up on part numbers. Next time, Pete

thanks Pete, that’s a good recollection. That’s a lot of power from C55s - Or do Cs flow more than Ns? Mine is rated 300 or so but that’s in marine application, not what the torque curve will be like on the road. It’d be good to know what it was built with originally, but it seems like standard timing is the go for me.

Overlander's Pic of the Build, with Allison Trans.

Pretty sure C is for coach and 55 is the volume of the injector

Also am lead to believe that as injector volume increases the stroke of the injector is longer hence the timing has to be more advanced so it has slightly more storke before it fire's

But I'm definitely no expert at all and dont really know my ass from my elbow about these

Paul

PaulFH wrote:

Overlander's Pic of the Build, with Allison Trans.

Now thats a clean Detroit, mind you I think if they are in good nick they are pretty clean

Paul

As i recall............
The C or N is the characteristic of the fuel delivery.........variable or sharp
start or stop etc............
The height setting is the start of injection ( hence timing )...............
The 55 bit is the volume of fuel delivered over 1,000 strokes in CCs.............
The amount of fuel squirted in is determined by the injector build up.
All this is subject to a failing memory...............
.................Billy..............

Wedgetail I'm not 100% certain but I think I was told in my youth that the C as in C55 refers to 'Clean' tip- an upgrade from N55 injectors to attempt to have the Greta's of the 70's pacified. I wouldn't put money on it though. The photo of the 6v53T was taken after a full engine & transmission dyno [to ensure the shift points on the trans are in spec} and paint shop to give the engine a good as new look. We took pride in our finish of each 6v53 and if you put a rebuilt engine from the other 2 branches that the Defence dept allocated them to you could easily distinguish the Adelaide built engine from the Altona or Townsville engine by our 'signature' finish- little things like lining up all the cable ties, painting the valley before installing the blower & painting the back of the cylinder heads and other things.. I also wanted the young fella to absorb the pride before passing over my build book so he continues the standard. He has.